From exit 230 on I-5, get on Route 20 headed west (away from the mountains). Follow the signs on Route 20 towards the Anacortes ferry (do not take the spur of Route 20 that heads towards Oak Harbor). The highway will turn onto Commercial Street in Anacortes. Follow Commercial Street until you reach the Safeway. At that intersection, turn left onto 12th Street and stay on 12th Street (which changes names to Oakes Avenue) for about 4 miles to the light above the Anacortes Ferry Terminal. Go straight through that light onto Sunset Drive. About 0.25 miles past the light, make a right turn onto Shannon Point Road (if you reach Washington Park, you missed the turn). Follow Shannon Point Road to the end and park. Follow the path from the parking lot to the Shannon Point Marine Center main entrance.

From the Anacortes Ferry Terminal:

Upon leaving the ferry terminal, follow the road up the hill to the traffic light. make a right hand turn onto Sunset Drive. About 0.25 miles past the light, make a right turn onto Shannon Point Road (if you reach Washington Park, you missed the turn). Follow Shannon Point Road to the end and park. Follow the path from the parking lot to the Shannon Point Marine Center main entrance.